INTRODUCTION: The Introduction portion of this proposal provides a general overview of the entire proj ect including Aims, Background, Preliminary results, and our Methodological approach. Our overall strategy to achieving the goals of the Alzheimer's Disease Neuroimaging Initiative (ADNI) are described, as well as a specific plan for implementation including governance structure, deliverables and timelines. ADMINISTRATIVE CORE: The Administrative Core, is directed by Dr. Michael Weiner, PI of the entire ADNI application, based at UCSF. This Core will be responsible for overseeing all aspects of the entire ADNI including the monitoring all financial and budetary aspects of the project. INFORMATICS CORE: The Informatics Core (IC), based at the Laboratory ofNeuroimaging (LONI) at UCLA will be directed by Dr. Arthur Toga. The IC will be responsible for receving, archiving, and displaying all MRI and PET data including all raw and processed data. All of this data will be available to ADNI investigators, and to the general public within weeks-months after receipt. The IC also describes a number of informatics and image processing and image display tools which will be used by the ADNI. Finally, the IC describes mechanisms by which clinical and cognitive data, stored at the UCSD ADCS group will be linked to the image data at LONI. This will facilitate queries and analyses which utilize clinical, cognitive, and imaging data. All raw and processed image data, as well as all clinical and biomarker data, will rapidly be made avialable on public websites. BIOSTATISTICS CORE: The Biostatistics Core (BC) will be directed by Dr. Laurel Beckett at UC Davis, and will consist of statisticans at UCSD and UCSF as well. The BC will implement mechanisms for data monitoring as data is acquired, to identify outliers and errrors. In addition, the BC describes a statistical approach to analyze data acquired by the ADNI, in order to test the apriori hypotheses described in the proposal, and presents a power analysis to justify the proposed sample size.